Cord-suspension electric dental engine.



PATENTED JULY 24, 1906.

J. V. TRENAMAN.- CORD SUSPENSION ELECTRIC DENTAL ENGINE.

APPLIOATION FILED JULY 21, 1906.

INVENTOR ,jzfin f z zvzamam ATTORNEYS telescopic joint 11 and is JOHN V. TrtENAMAN, .OF NEW YORK. N. Y. CORD-SUSPENSION ELECTRIC DENTAL ENGENEE Specification of Letters Patent.

Patented July 24. 1906.

Application filed July 21. 1905. Serial No. 270,658.

To wZZ whom it may concern:

Be it known that I, JOHN B. TRENAMAN, a citizen of the United States, and a resident of the city of New York, borough of Manhattan, in the county and State ofNew York, have invented a new and Improved "Cord- Suspension Electric Dental Engine, of which the following is a full, clear, and exact description.

My invention relates to means for mounting and manipulating dental engines, and more particularly to the means for suspendingthe electric motor and its accompanying parts.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the views.

Figure 1 is a side elevation showing my inventipm ready for use. Fig. 2 is a vertical section through the motor-casing and immediate connections thereof, and Fig. 3 is an enlarged cross-section through the cord connected with the motor mechanism.

Mounted upon a wall 4 is abracket 5, pro vided with a pin 6, projecting upwardly therefrom. A cylindrical bearing-sleeve -7 is journaled upon this pin and is provided .with' an arm 8, projecting laterally therefrom and disposed horizontally. This arm has ,a provided with brackets 9 and 10. These brackets support pulleys 12 and 13, over which passes a flexihis connection 14. Mounted upon one end of this flexible connection is a counterweight 14 for balancing the motor mechanism, the motor-casing of which is shown at 15 and is made in halves. The lower half of the casing is provided with a ring 16, which encircles a coupling 17, provided with a centering-pin 18 for the purpose of engaging and rotating a flexible shaft 19, which is inserted in the usual manner through a tubular member 19 The coupling 17 also serves as joint, as does also the tubular member 19%.

The motor is shown at 20 and is provided With brushes 21 22, made in the usual or any preferred manner. This motor is provided with a spider 23, and extending up wardly from this spider is a dome 24, pro vided with an opening 25. Fitting within the-dome is a hemispherical bearing member 26, provided with acylindrical aperture 27 coincident with its axis. This hemispherical bearing member 26 is integral with another dome 28, aswillbe seen from Fig. 2. Acap 29 end of the dome 28,

an insulatingis provided with a threaded annular portion 30, which is screwed into the upper or large the latter being threaded for this purpose. A sleeve 31 of insulating 6o material is bushed into the cap 29.

Mounted within the dome 28 and fitting neatly against the lower edge of the annular portion 30 is a washer 32 of'insulating material, preferably hard rubber. This washer is provided with apertures 33, through which pass conducting-wires 35, and is also provided with a comparatively large central aperture, through which passes a braided cord 34, provided at its inner end with a head or knob 34* to prevent its withdrawal from the washer. The conducting-wires 35 lead upward from their connection with the various binding-posts 36 and brushes 21 22 in the usual and said wires after passing manner, through the washer 32 are carried to an engagement with the cord 34 and are braided thereupon in the usual orany suitable manner.

My invention relates more particularly to the mechanism shown in the upper portion of Fig. 2 and used for .sustaining the weight of the motor. Referring to this figure, it will be seen that the entire weight of the motor and parts connected immediately there- 5 with bears upon the dome24, and the consequent downward pull of this dome is sustained upon the hemispherical bearing member or head 26. The aperture 25 is of suflicient size to enable'the bearing member or head 26 to havea reasonable degree of angular movement, so that the motor-casing 15 and its contents may be swung slightly in any. direction. The washer 32 serves as a spreader for holding the wires 35 apart. The entire weight of all the heavy parts is thrown directly upon the cord 34, no part of it being upon the conducting-wires and all danger of breaking these wires is therefore avoided. The device is neat in appearance and materially increases the quality of the insulation as between the wires and other metallic parts. My invention is used as follows: The motor being mounted as above described, it may be raised or lowered by manipulating the counterweight 14*, a flexible shaft being connected with the motor in the usual manner and electric power being turned on the motor is actuated in the manner well understood, this driving the flexible shaft. The operator can swing the motor bodily by means of the arm 8 an can also lengthen or shorten this arm.

Without disturbing the position of the arm or either of the pulleys, however, he can cause the motor to turn to divers angles, as above described, the action being somewhat simi.

lar to that of a swivel-joint. of flexibility is thus secured and the danger of causing a kink or buckle to take place in the flexible shaft 19 or in the conducting Wires or flexible suspension member 14: is ob viated.

Having thus described my invention, I

' claim as new and desire to secure by Letters said suspensory member and said conducting-wires.

2. In an apparatus of the character described, the combination of a suspensory member provided with an'enlarged portion, a washer through which said suspensory -member is threaded, said washer engaging 5c scribed, the combination of a motor, a. memsai denlarged portion, and a motor provided with mechanism having a portion for engaging said washer. v 3. In an apparatus of the character described, the combination of a washer provided with apertures, a vsuspensory member engaging said washer by aid ofone of said apertures, conducting members passing throrwh others of said apertures, a member encircling saidwasher, and a motor connected with said member and sustainedthereby. 4. In an apparatus of the character de. scribed, the combination of a cap, a dome connected with said cap and provided with a hemispherical head, conducting-wires passing through said cap, means for supporting said cap, and a motor provided witha suporting-dome engaging said hemispherical ead, said motor being provided with -electrical connections for engaging said conducting-wires.

5. In an apparatus of the character de- A great degree ber connected therewith and provided with 1 a-hollow dome, a bearing member partially encircled by said dome and movable relatively thereto after the manner of a swivelelectrical connections for energizing said motor.

6.. In an apparatus of the character described, .the combination of a suspensory member, awasher mounted thereupon and passing through said. apertures and disposed parallel with said suspensory member, a jacket common to said suspensory member and to said wires, and motor mechanism .connected with said wires and energized thereby.

7. In an apparatus of the character de vided with a supporting member connected thereto, a dome connected with said supportingmember and provided with anaperture, a member provided with a head inserted within said dome and movable relatively with a neck passing through said aperture, means for suspending said member, and electrical connections mounted partially within said dome for energizing said motor.

8. In an apparatus of the character described, the combination of a dome provided sage extending entirely through said dome and said hemispherical head, a cap connected with said dome and closing the'same, a washer mounted within said dome and engaging said cap, means for supporting said washer, con

and through said passage, and a member engaging said hemispherical headior the purpose of supporting a motor,'said conductingwires being connected with said motor for the purpose of energizing the same. In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses. I JOHN V. TRENAMAN.

l/Vitnesses:

F. W. HANAFORD,

EV'ERARD BOLTON MARSHALL.

joint, means for supporting said member, and

scribed, the combination of a motor prothereto, said member being further provided.

with a hemispherical head and with a pasprovided .with apertures, conducting-wires ducting-wires passing through said washer 

